The most effective way to remove grease stains from laundry is to treat the stain with a dishwashing detergent that is formulated to remove grease. Rub it into the stain, let sit for a few minutes, then wash as usual. Waterless mechanic´s soap (from an auto-parts store) is also very effective at cutting grease. Grease is very effective at removing grease, so you could also rub Crisco into the stain, then launder.
